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Lightning Strike Help

Had a lightning strike real close and fried a circuit board and transformer in upstairs furnace (Armstrong Ultra SX80). Contractor replaced parts, left, still no cold. Contractor returned same day a to find outside 'compressor shorted to ground and positive acid test in refrigerant'. Quoted on the spot for a replacement condenser for the upstairs system (currently Armstrong 2.5 ton 11-12 years old Seer 10).

Contractor recommendation was for a Goodman 2.5 ton Seer 13 but they didn't do any sizing work that I could see...

In the previous 6 months I have had the Evap Cooler on the same system replaced with a Trane Seer 13 due to 'leak' in the old cooler.

Know that I need to seek additional quotes but do I need to have a Trane Seer 13 Condenser to match the Trane Evap Cooler or will any Seer 13 equipment match up OK.?

I'd match the system too but if the burnout was bad, insurance should replace the indoor coil & lineset. They are contaminated and even trying to clean up could leave some acid behind that could cause problems later.

I'd match the system too but if the burnout was bad, insurance should replace the indoor coil & lineset. They are contaminated and even trying to clean up could leave some acid behind that could cause problems later.

I'd match the system too but if the burnout was bad, insurance should replace the indoor coil & lineset. They are contaminated and even trying to clean up could leave some acid behind that could cause problems later.

Compressor and equipment is running during a thunderstorm. Lightning strikes nearby...does not even touch the power lines. The electromagnetic pulse sent out by a lightning strike spikes the voltage supply to the house, frying circuit boards and etc. Compressor windings see spike, dielectric resistance between windings overcome, windings either short to one another or short to ground, creating an arc fault inside the compressor dome. Arcing is burning, creating acid in compressor oil (which is always on windings and etc.) Before compressor stops running completely, it manages to pump enough burned oil throughout the system to warrant an extensive clean-up or replacement of various refrigerant circuit components.

If lightning directly strikes the power supply, it's beyond obvious why everything fries. The above was to illustrate that lightning does not need to directly contact the power supply or structure to cause damage. I personally witnessed this at one of my former houses...lightning sailed right over the power lines in the alley behind our house, without hitting it, spiking the voltage and taking out our furnace circuit board. Fortunately we had unplugged our computers and other electronics, as we always try to do when a thunderstorm blows up, so nothing else was lost.

SH
We share the same initials just they stand for different nick names I would say pseudonym but in my case that might be less than truthful.

Since Florida is the USA lightning capital I'm pretty familiar with the many ways of lightning. But are you talking about transient voltage causing acid in the refrigerant system? So it's not always moisture that creates the acid well that makes the cheese all the more binding.

Moisture turning oil acidic will create a condition whereby the acid erodes the winding insulation. WHAM! Compressor shorts windings or shorts to ground. A violent spike in voltage, enough to take out the windings, will create an arc fault and motor winding burnout...the oil will be shot to hell as it is already in contact with the windings, and until the pump stops running it will spread the mess throughout the entire system. Just my ascertation on the scenario. I know there's folks better informed on the subject than I.

Moisture turning oil acidic will create a condition whereby the acid erodes the winding insulation. WHAM! Compressor shorts windings or shorts to ground. A violent spike in voltage, enough to take out the windings, will create an arc fault and motor winding burnout...the oil will be shot to hell as it is already in contact with the windings, and until the pump stops running it will spread the mess throughout the entire system. Just my ascertation on the scenario. I know there's folks better informed on the subject than I.

I got that but will this system with no acid prior to the lightning damage test positive for acid. The reason I'm asking is the insurance companies will often times deny claim if acid test is positive.

I got that but will this system with no acid prior to the lightning damage test positive for acid. The reason I'm asking is the insurance companies will often times deny claim if acid test is positive.

Good question...next time I encounter a burned out compressor I should slap a test kit on the refrigerant before recovering it. Of course, it could still be argued that moisture was in the system prior to burn out, but that can also be tested for. Reason I mention testing a compressor burnout sans lightning strike is for determining if a burnout alone would turn the oil acidic. It'll put a hell of a lot of carbon into the oil, and by the way compressor oil smells that is from a compressor burn out (very pungent) would indicate to me it is acidic in nature.

Someone out there likely has data indicating what exactly occurs to compressor oil during a burnout. Most relevant would be data indicating moisture levels in system prior to burnout at or below accepted levels for the specific refrigerant and compressor oil, eliminating moisture as the aggravating factor. Further, that the burnout was deliberately caused for observation purposes via overvoltage to the motor windings.

Thanks for all the help from everybody who replied.....Now that I know that I probably will be having the coil and line sets replaced as well what would be the pros and cons of having the 12 year old Armstrong furnace replaced while
having everything else done.

Have had no problems with this unit at all up until this point. And Iraq Veteran....it is quite a funny looking fellow up in the Attic!